My girlfriend and I have been happily in a relationship for 2.5 years. We understand each other and have many similar interests. We are truly each other’s best friend. She suffers from severe anxiety, and it has its strains on the relationship, but nothing we can’t work on together.
Her parents bought a duplex for us/me to rent to own. Honestly I’m happier here than I have been in a long time. But she won’t move in. She claims she doesn’t want to be a financial burden, but I make $80k/year so it’s not justifiable. She spends lots of time over, but she still lives with her parents, and she freaks out when I bring it up. I’m ready for our relationship to move forward into a partnership, but it’s obvious this scares her so much. It’s been five months now. How do I convince her that it’s time to move forward?
LemonVibe 
I read somewhere that it takes a few years (3-4) to really get to know somebody, so maybe you guys are transitioning into the phase of really getting to know each other.
Moving in together brings about a whole new set of responsibilities, and maybe she’s afraid of what can possibly happen if you move in (i.e losing interest in each other because of being together all the time, finding out something you don’t like about the other, etc.)? Which are normal fears, but after 2.5+ years, you both deserve the honesty and openness.
I say the best thing to do is to be straight up with her and ask her in a gentle way if the idea of living together makes her uncomfortable, and if so, what can you both do to assuage any concerns.
If she’s afraid that it’s all happening too fast, then compromise and ask for sleepovers a couple of times a week (like maybe she can spend a weekend with you once every couple of weeks).
If you and your partner are not on the same page, the concern should lie in figuring out why they fell behind in the first place and then helping them catch up (if they want) because maybe it’s a lot to take in and/or maybe you’re reading too fast compared to them. Communication is key. Just be sensitive and open.